Ink jet printers generally have a ‘jet stack,’ a stack of thin, brazed steel plates that have manifolds to route the ink from ink reservoirs to an array of jets from which ink is dispensed. The jet stack represents a substantial portion of the overall printer cost. Reduction of costs has resulted in reducing the size of the jet stack. Reducing the size lowers the amount of material needed, processing and shipping costs. This smaller size results in less room to fit the geometries for venting, printing, aligning and sequencing features. The assembly process needs the aligning and sequencing features to ensure that the plates are in the proper order and aligned correctly. Misaligned or out of order plates result in malfunctioning and/or lower efficiency print heads.
Currently, a sequencing feature referred to as ‘stair steps’ assists in ensuring the plates are stacked in the proper order. An edge of each plate has a tab of differing widths so that the stacked plates form a ‘stair step’ similar to stacked file folders or an index on the edge of the pages of a book. In addition, an alignment feature that ensures correct alignment in addition to the correct sequence also typically exists on the jet stack. U.S. Patent Application Publication US20080259121 shows an example of such an alignment feature.
These sequencing and alignment features take up quite a bit of real estate on the plates. This then contributes to larger jet stack plates, resulting in higher costs and larger print heads for a given print density.